Solar cells are well known devices for converting solar radiation to electrical energy. They may be fabricated on a semiconductor wafer using semiconductor processing technology. A solar cell includes P-type and N-type diffusion regions. Solar radiation impinging on the solar cell creates electrons and holes that migrate to the diffusion regions, thereby creating voltage differentials between the diffusion regions. In a back contact, back junction (BCBJ) solar cell, the P-type and N-type diffusion regions and the metal contacts coupled to them are on the backside of the solar cell. The metal contacts allow an external electrical circuit to be coupled to and be powered by the solar cell.
To compete with other energy sources available on the market, solar cells not only have to be efficient but also fabricated at relatively low cost and high yield. Although solar cells can be fabricated using silicon processing steps, operations performed on a silicon wafer necessarily occur after the wafer has been created. Creating silicon wafers for solar cells typically can include, for example, forming a silicon material, shaping the silicon material into an ingot, and wafering the ingot to form silicon wafers. Embodiments of the present invention pertain to novel solar cell fabrication processes and structures that reduce the cost of solar cell fabrication.